Transportation of hydrocyanic acid



F. J. METZGER. TRANSPORTATION OF HYDROCYANIC ACID. APPLICATION FILED JAN. 27, 1920.

1,408,757, Patented M r. 7, 1922 lll 51 g: 255 Mo mac t s FLOYD J. METZGER, OF NEW YORK, I\T. ll,

ASSIGNOR TO AIR REDUCTION COMPANY,

INCORPORATED, A CORPORATION OF NEW YORK.

TRANSPORTATION OF HYDROCYANIC ACID.

Specification of Zetters Patent.

Application filed January 27, 1920. Serial No. 354,419.

To all whomit may concern:

Be it known that I. FLOYD J. Mnrzonn, a citizen of the United States, residing at New York, in the county of New York, State of New York, have invented certain new and useful Improvements in the Transportation of Hydrocyanic Acid; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the artito which it appertains to make and use the same.

This invention relates to fumigation. and particularly to-the transportation and use of hydrocyanic acid for this purpose.

An object of the invention is the provision of a vessel for hydrocyanic acid in which it may be safelytransported, which will ahsorb and neutralize hydrocyanic acid acci dently released, and from which the hydrocyanic acid may be readily withdrawn for use.

Further objects and advantages of this invention will be apparent as it it better understood by reference to the following specification when read in connection with the,

accompanying drawing illustrating the preferred embodiment of my invention, in which- Fig. 1 is a longitudinal section through a container for hydrocyanic acid; and

Fig. 2 is a section on the line 2--2 of Fig. 1.

Hydrocyanic acid has been used heretofore as a fumigating material to destroy germ, insect and animal life. Use of this material has, however, been restricted because of the necessity of generating the hydrocyanic acid in situ, by the treatment of an alkali metal cyanide with sulphuric acid. This method is unsatisfactory, involving as it does the handling ofn'eagents .such as sulphuric acid and the carrying out of a chemical reaction under unfavorable conditions.

Under such conditions, the available hydrocyanic acid not efiiciently released and a sludge containing decomposition prod ucts, sulphuric acid and more or less poly- 'merized. hydrocyanic acid remains; This sludge is inherently dangerous and is disposed of with difficulty. Furthermore, the floors, walls and furniture of the room or enclosure in which the reaction is carried out are'ftre quently' damaged by the sulphuric acid; and workmen are sometimes injured agents to be mixed at the place to be fumi gated, sulphuric acid is eliminated and the only manipulation required is the placing of the hydrocyanic acid or solution thereof in suitable receptacles from which it is to be evaporated.

The hydrocyanic acid is advantageously transported in'containers holding a unit charge sufiicient to fumigate a room, having a capacity, for example, of one thousand cubic feet. The size of the unit charge is of course arbitrary and may be varied. The hydrocyanic acid in such a charge may be Patented Mar. "3, 11922.

in liquefied form or it may be in a water solution thereof. In practice I have found that a 75% solution of hydrocyanic acid is very desirable since it does not develop material pressure in a closed container at nor-.

mal atmospheric temperature, but, nevertheless, readily vaporizes when exposed to the atmosphere. Thus when such a solution is poured into an open receptacle and exposed in a room or enclosure the entire charge will evaporate within a short time, which may be lessened by employing a wick to increase the evaporating surface.

Hydrocyanic acid is a dangerous material unless its use is carefully safeguarded. The fact that it evaporates spontaneously when exposed to the atmosphere makes it necessary to observe due precaution to prevent accidental escape of the acid from the container in which it is transported. Glass or ceramic containers are preferably employed because metals are slowly attacked by the acid. -Itis desirable, therefore, to provide means to absorb and neutralize any hydrocyanic acid whichma-y escape from the container and particularly in the event of breakage of the container it is essential that all of the hydrocyanic acid be held and tralizing means surrounding the container and disposed Within a suitable casing therefor. For this purpose ll prefer to employ a "mixture of absorbent carbon or charcoal and slaked lime (calcium hydroxide) in which a quantity of Water is preferably absorbed to render the material more active. Ether 4 absorbent materialmay be used. For esa ple, caustic soda (sodium hydroxide) may be substituted for the slaked lime in the-2mm ture; slaked lime without carbon may be employed; and sawdust or kieselguhr, may

be substituted for the carbon.

When hydrocyanic acid is released in contact with slaked lime or mixtures such as are above described, a part of the hydrocyanic acid is absorbed; a part is chemically neutralized; a part may be hydrolyzed, and another part may be polymerized. Io exact explanation of the mode by which the hydrocyauic acid becomes inefi'ective is possible or necessary, and any or all of these functions may be carried out in the mass simultaneously or successively. It is a fact, however, that a sufiicient supply of the slaked'lime or mixture Will prevent the escape of hydrocyanic acid to the atmosphere.

Referring to the drawing in which I have illustrated by way of example, one form of a transportation vessel adapted to accomplish the desired "result 5 indicates a glass or other suitable container, 8 oz. bottle ,bein sufiicientl lame to contain the unit charge above described. The container s preferably provided with a stopper 6 and rubber gasket 7,-"the stopper being held in place by the common form of locking device 8, frequently employed in soda Water bottles. The container 5 an outer casing 9 which may be made of paper, metal or wheat-suitable material and is preferably closed by a screw cap 10. A cage 11 which may beconstructed or" Wire, for example, may bejprovided to hold the container '5 centrally within the casing 9, the legs 12 of the cage bearing against the Wall of the casing.

The space within the 9 and about the containerii is filled with absorbent ma terial 13 and in preferred embodiment of my inventionl employ jt'our parts by weight of absorbent carbon or (sliaifco four (4) parts by weight of slahed li cium hydroxide) and three (3) weight of Water, the whole being JlRQFOUglllf/ mixed prior to disposal Within the 9. The-amount of water used is not cut to moisten the material p-erceptibiy, out serves to hasten absorption of hydro-- cyanic acid. is to be unrlerstcoc.

disposed Within contaii'ier.

proportions may be varied and that active materials may be substituted for those mentioned to accomplish the primary purpose of the in vention.

In the practical application of my invention, 1 have found that entire charge of hydrocyanic acid sufficient to fumigate a room of one thousand cubic feet capacity may be released the surrounding material as hereinbefore described and that no ellective amount hydrocyanic acid will escape. Tao breakage of container, therefore, even in a confined space is immaterial and the otherwise dangerous acid is rendered harmless- From the foregoing it will be readily understood thatl have cerfected means which makes the use oi hydrocyanic acid as a fumigating agent practically possible. In the container protected as above described the acid be safely transported by and in common carriers without danger to e1nployees or the public generally. To use the acid it is necessary merely to remove the screw cap 10 withdraw the container, open the same an pour the acid into a suitable receptacle, preferably a shallow tray, which may be provided with a wick to increase the evaporating surface.

Various changes be made in the form and arrangement of the vessel and in the material employed without departing fronr the invention or sacrificing any oi its ad- Vai tages 1 claim:

1. A transportation vessel for hydrocyanic acid, including a container for the acid, and a neutralizing compcsition comprising); an absorbent and 3,.121a-terial capable of reacting chemically with said acid, said composition being disposed about said oontainer. I y

2. A traaisporta-tionvcssel for hydrocyanic acid, including a container for the acid, and a neutralizing composition comprising absorbent carbon and a material capable cireacting; chemically with said acid, said composition being disposed about said container.

3. A transportation cyanic acid, acid. and neutralizing composition'comprising an absorbent and calcium h droxide, said composition being}; disposed a out said vemel for hydro- 4. A transi oortation vessel for hydrocyanic acid, including a container for the acid, ceiitraliaiiig composition cone prising" absorbent carbon and calcium'hyrozzidc, said composition being disposedabout aid container.

15. transportation vesselfor hydrocyanic acid, includ' -g a container for the acid, and ueutrhaing composition comcarbon and calciiim hyincluding a container for the V droxidc, said composition containing in addition a proportion of moisture and being disposed about said container.

6. A. transportation vessel for hydrocyanic arid, including a container for the acid, and a neutralizing composition containing an absorbent, a material capable of combining chemically with said acid and a proportion of moisture, said composition be ing disposed about said container.

7. A neutralizing composition for hydrocyanic acid, comprising an absorbent and a material capable of combining chemically with said acid.

8. A neutralizing composition for hydrocya nic acid. comprising an absorbent material and calcium hydroxide.

9. A neutralizing composition for hydrocyanic acid, comprising absorbent carbon and a material capable of combining chemi-' cally with said acid.

10. A neutralizing composition for hydrocyamc acid, comprising absorbent carbon and calcium hydroxide finely divided and 

